Yesterday, while attending a luncheon at a Cleveland party center, I stopped by the bar to ask about tipping policies.

I do this because I learned a decade ago that sticking a tip into a jar does not necessarily mean the gratuity goes to the person who is serving you.

This is true where you live, too. I’ve learned that from experience, too. Regardless of what city I’m visiting, it’s a fair bet that I will find yet another story about yet another restaurant or banquet hall that skims — no, let’s call it what it is: steals — tips from servers, valets and bartenders. Most of them are hourly wage earners who depend on tips to make minimum wage.

Businesses get away with this egregious practice because most patrons never think to ask, especially when the jar on the counter says “tips.” Never trust that little sign, by the way. My first column on this issue, in 2004, was about a large jar marked “tips” at a coat check in Cleveland. After making small talk with the weary clerk behind the counter, I discovered that not a cent of the jar brimming with bills went to her or her co-workers.

When I called the party center the next week to ask how that could be, three different managers told me, “Nobody cares who keeps the tips.”

Boy, were they wrong.

This week, sure enough, the bartender had a similar story. In this case, she was allowed to keep cash tips. She wanted me to know, however, that tips left on charge cards never found their way to her or other servers.

All too common practice: Customers mistakenly think that mandatory “service charge” is the tip, or they leave the gratuity on the charge card but don’t make clear that it’s intended for the men and women who waited on them.

Yes, I know. You would think that if you write the gratuity next to the word “tip,” everyone would agree on who’s getting that money. The only way to be sure it goes to the service employees is to insist.

Better yet, check on the policy before you book your event — and spread the word if you find out they don’t treat their servers fairly. Nothing changes bad business practices faster than a bunch of potential customers making clear why they’re taking their business elsewhere.

Something else you should know about tips left on charge cards: In many restaurants, managers deduct from tips the service charge they must pay credit card companies.

That’s why, whenever possible, you should tip in cash.

Why am I reminding you of all this now?

The holiday season is in high gear, and many of us will be eating out — and hosting or attending catered parties — more than usual. Most of the people waiting on us are never going to start that conversation about who gets the tips. Experience has taught me that most of them are grateful when a customer bothers to ask.

There’s another reason I’m writing about this now.

Last week, the media — social and mainstream — were all abuzz over a series of tweets by TV producer Elan Gale. Casting himself as a hero to the downtrodden, Gale posted a series of increasingly misogynist exchanges meant to illustrate how he had rightly humiliated a woman who deserved our collective wrath for mistreating an airline attendant — and him.

The website BuzzFeed’s take — “This Epic Note-Passing War On A Delayed Flight Won Thanksgiving” — pretty much sums up the celebratory mood.

Only after a few writers started challenging the veracity of his tale did Gale admit it was a hoax, sparking another round of what-have-we-come-to hand-wringing in my profession. BuzzFeed issued an “update,” which is what too many journalists call a correction these days. It’s come to that.

However, in my never-ending quest to find the upside to unfortunate examples of human behavior, I’ll say this for Gale: He did give us an opportunity to think about how we should advocate for someone who’s being mistreated.

As rules go, this one’s as universal as it is simple: Don’t be a jerk.

No, let’s go out there and make somebody’s day.

Connie Schultz is a Pulitzer Prize-winning columnist and an essayist for Parade magazine.